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941.
A study of water quality, land use, and population variations over the past three decades was conducted in eastern Massachusetts
to examine the impact of urban sprawl on water quality using geographic information system and statistical analyses. Since
1970, eastern Massachusetts has experienced pronounced urban sprawl, which has a substantial impact on water quality. High
spatial correlations are found between water quality indicators (especially specific conductance, dissolved ions, including
Ca, Mg, Na, and Cl, and dissolved solid) and urban sprawl indicators. Urbanized watersheds with high population density, high
percentage of developed land use, and low per capita developed land use tended to have high concentrations of water pollutants.
The impact of urban sprawl also shows clear spatial difference between suburban areas and central cities: The central cities
experienced lower increases over time in specific conductance concentration, compared to suburban and rural areas. The impact
of urban sprawl on water quality is attributed to the combined effects of population and land-use change. Per capita developed
land use is a very important indicator for studying the impact of urban sprawl and improving land use and watershed management,
because inclusion of this indicator can better explain the temporal and spatial variations of more water quality parameters
than using individual land use or/and population density. 相似文献
942.
Defining agents' behaviors to simulate complex residential development using multicriteria evaluation 总被引:4,自引:0,他引:4
Cellular automata (CA) have been increasingly used to simulate complex geographical phenomena. These models may have limitations on reflecting individuals' behaviors which should be considered in urban simulation. Agent-based modeling can solve some of the problems in addressing individuals' influences in urban systems. However, there is a general lack of methodology on how to define agents' properties. This paper uses multicriteria evaluation techniques to determine some of the parameters for the agent-based model. Empirical data from GIS are used to define agent's properties. Sensitivity analysis is also carried out to assess the influences of parameters on simulation outcomes. This model has been applied to the simulation of the residential development in a fast growing city, Guangzhou, in south China. 相似文献
943.
944.
Fang Chen Ping Liu Ying Gu Zhu Zhu Amulya Nanisetti Zhangzhang Lan Zhiwei Huang Jia Sophie Liu Xiongbin Kang Yuqing Deng Liqiong Luo Dan Jiang Yong Qiu Jianchang Pan Jun Xia Ken Xiong Chao Liu Lin Xie Qianyu Shi Jing Li Xiuqing Zhang Wei Wang Snezana Drmanac Lars Bolund Hui Jiang Radoje Drmanac Xun Xu 《黑龙江环境通报》2017,37(13):1311-1321
945.
根据2011年5月~2013年11月莱州湾海域表层海水中石油类污染状况进行的现场调查,研究分析了莱州湾表层海水中石油类的平面分布和季节变化特征。结果表明,2011~2013年,莱州湾表层海水中石油类的浓度变化范围分别为0.009~0.101mg/L、0.00875~0.0879mg/L和0.0118~0.0687mg/L,石油类含量总体年际变化不大,但2011年与2012年、2013年呈现不同的季节变化,2011年夏季(8月)高于春季(5月),而2012年~2013年表现为春季>夏季>秋季(5月 >8月 >10月 >11月)。从石油类的平面分布来看,基本呈现近岸高、湾中部及湾口低的特点,高值区主要集中在小清河口和黄河口等河口附近海域。 相似文献
946.
947.
Economic Development and Conservation of Biological and Cultural Diversity in Yunnan Province, China
Rey C. Stendell Richard L. Johnson John P. Mosesso Xia Zhang 《Environment, Development and Sustainability》2000,2(3-4):333-345
Chinese and American scientists are co-operating to develop concepts, strategies, agreements, and proposals in support of an economic development and sustainable ecosystems project in Yunnan Province, People's Republic of China. Yunnan's Provincial Government has initiated a major programme to develop and further utilise its biological resources to help improve economic conditions for its citizens. They are co-operating with the US Geological Survey (USGS) on evaluation and management of biological resources so economic development will be compatible with sustainable ecological systems. Scientists from the USGS and co-operating universities will provide expertise on synthesising biological data, conducting a Gap Analysis for the Province, evaluating innovative economic opportunities, and designing an effective education, training, and outreach programme. 相似文献
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950.